Mining and large scale excavating operations may require fleets of haulage vehicles to transport excavated material, such as ore or overburden, from an area of excavation to a destination. For such an operation to be productive and profitable, the fleet of haulage vehicles must be efficiently operated. Efficient operation of a fleet of haulage vehicles is affected by numerous operation characteristics. For example, the grade and character of haul routes and the amount of payload have direct effects on haulage cycle time, equipment component wear, and fuel consumption which, in turn, directly affect productivity and profitability of the operation.
In order to reduce inefficiencies in the operation of the haulage vehicles, the vehicles may be provided with technology for monitoring various operation characteristics. Data from monitoring equipment may be collected, processed, and compared to a standard in order to determine any corrective measures that may be desired or required.
One method of controlling an automobile based on one or more sensed operating characteristics is described in U.S. Pat. No. 5,510,982 (the '982 patent) issued to Ohnishi et al. The '982 patent describes a method for automatically selecting a predetermined shift gear based on a stored preset shift pattern. The shift gear may be selected based on a sensed vehicle speed, a sensed throttle valve opening, an estimated vehicle weight, and an estimated running load.
The system of the '982 patent provides a system for autoshifting a transmission of an automobile based on operation characteristics that are sensed in real time. Such a system may shift into a lower gear over relatively steeper portions of the terrain and then shift into a higher gear over relatively flatter portions of the terrain. However, since the system operates based on characteristics that are sensed in real time while the automobile is traveling along its route, the system may tend to “gear hunt” in situations such as when traveling over bumpy terrain. In such situations, the system may repeatedly shift between first and second gears without providing any significant advantages with respect to speed or fuel consumption. Each shift may result in a loss of energy, and the transmission may operate less efficiently when shifting than when operating in gear. This may result in slower cycle times, greater fuel use, and a less efficient operation of the automobile.
The disclosed method is directed to overcoming one or more of the problems set forth above.